Pre-constricted prosthetic heart valves

ABSTRACT

An improved holder and storage system for prosthetic heart valves that pre-shields or pre-constricts the commissure posts of the valve to prevent suture looping. Pre-shielding and pre-constriction mean at the time of manufacture, so that the valves are stored with the commissure posts shielded and/or constricted. The holders may have solid legs that directly contact and constrict and hold the commissure posts without the use of sutures in tension that might creep over the time in storage. The holder may have a base in contact with the inflow end and a shaft portion that projects through the valve leaflets and cooperates with movable legs on the outflow end of the valve in contact with the commissure posts. The holders may, alternatively, have flexible leg members that extend through the valve and have distal end portions configured to extend over and shield the tips of commissure posts.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/639,646, filed Jun. 30, 2017, now U.S. Pat. No. 10,588,743, which isa divisional of U.S. patent application Ser. No. 13/948,923, filed Jul.23, 2013, now U.S. Pat. No. 9,693,862, which claims the benefit of U.S.Patent Application No. 61/677,940 filed Jul. 31, 2012, and of U.S.Patent Application No. 61/779,890 filed Mar. 13, 2013, the entiredisclosures all of which are incorporated by reference herein for allpurposes.

FIELD

The present invention relates to holders and methods of holding andstoring that facilitate implantation of prosthetic heart valves bypre-shielding and/or pre-constricting the valve commissure posts.

BACKGROUND

Heart valve disease is a significant cause of morbidity and mortality,resulting from a number of ailments including rheumatic fever and birthdefects. The natural heart valves are identified as the aortic, mitral(or bicuspid), tricuspid and pulmonary valves, and each has leaflets tocontrol the directional flow of blood through the heart. Worldwide,approximately 300,000 heart valve replacement surgeries are performedannually, and about one-half of these patients receive bioprostheticheart valve replacements, which utilize biologically derived tissues forflexible fluid-occluding leaflets.

Heart valve prostheses are either of the mechanical type that originallyused a ball and cage and more recently a pivoting mechanical closure, ora tissue type or “bioprosthetic” valve typically constructed withnatural-tissue valve leaflets. The most successful bioprostheticmaterials for flexible leaflets are whole porcine valves and separateleaflets made from bovine pericardium stitched together to form atri-leaflet valve. However, flexible leaflets formed of polymeric,fiber-reinforced, and other synthetic materials have also been proposed.The most common flexible leaflet valve construction includes threeleaflets mounted to a peripheral support structure and commissure poststhat project in a downstream or outflow direction. The leaflets havefree edges between the commissure posts that meet or coapt in the middleof the flowstream to permit one-way flow. A suture-permeable sewing ringaround the inflow end typically provides a platform for anchoringsutures.

Prosthetic valves typically have a delivery holder centrally located andsutured thereto, and an elongated delivery handle coupled to the holderfor manipulating the valve assembly during implant. For the standarddelivery approaches, the holder is attached to the inflow side such asthe sewing ring for mitral valves and to the outflow side such as thestent cusps or outflow commissure tips for aortic valves.

When placing a flexible leaflet prosthetic valve in the mitral ortricuspid position, the commissure posts are on the leading or blindside of the valve during delivery and implant, and the surgeon uses theholder and an attached handle to slide (parachute) the valve down anarray of sutures that have been pre-installed around the mitral annulusand then passed through the valve sewing ring. The mitral position issuch that the outflow end with commissure posts is the leading end as itadvances toward the left ventricle during implantation, and thus theholder is attached to the inflow (i.e., trailing) end of the valve. Thedifficulty of the delivery task is compounded by the small accesspathway into the left atrium. Suture looping sometimes occurs when oneor more of the sutures in the parachute array inadvertently wraps aroundthe inside of one or more of the commissure post tips. If this occurs,the looped suture(s) may slow down the implant procedure, damage one ofthe tissue leaflets when tightly tied down, or interfere with valveoperation and prevent maximum coaptation of the valve leaflets,resulting in a deficiency in the prosthetic mitral valve. These issuedcan be resolved inter-operatively if the surgeon is aware of the suturelooping, but because the loops occur on the blind side of a mitral ortricuspid valve the surgeon might not be aware of a suture loop. If thesurgeon does not eliminate the suture loop and leaves a valve implantedwith a suture looped over the leaflet it is very likely to result inleaflet tearing forcing what can be an emergency surgery. If aftertearing initiates, it is not correctly diagnosed and treated theconsequences can be fatal for the valve recipient.

Existing mitral valve holders on the market attempt to mitigate thepotential for suture looping of the commissure posts during implantationby moving the posts toward the central axis of the valve (postconstriction). For example, U.S. Pat. No. 4,865,600 to Carpentier, etal., provides a holder having a mechanism that constricts the commissureposts inwardly just prior to implantation. The Carpentier deviceprovides an elongate handle to both hold the valve/valve holdercombination during implantation, as well as to cause the commissureposts to constrict inwardly. More recently, U.S. Pat. Nos. 6,409,758,6,702,852, 6,964,682, 6,966,925, and 7,033,390 disclose heart valveholder systems that resist suture looping.

Bioprosthetic heart valves configured for implanting in the aortic orpulmonic position also can benefit from constriction of the commissureposts. That is, although the holder attaches to the outflow side of thevalve, the lower radial profile of the commissure posts easesimplantation, such as through an aortotomy.

Bioprosthetic heart valves are conventionally packaged in jars filledwith preserving solution for shipping and storage prior to use in theoperating theater. Glutaraldehyde is widely used as a storage solutiondue to its sterilant properties. Because glutaraldehyde is a fixative,or cross-linking agent, and the fixing process is ongoing, bioprostheticvalves are stored in the jars with their leaflets in the closed orcoapting position and the commissure posts relaxed, not constricted.This is to ensure that the leaflets fix in the shape they are supposedto have when closed. Otherwise the leaflets may assume a distorted shapewhich could detrimentally affect functioning, such as regurgitation uponimplant. As a consequence, prior art devices that constrict thecommissures are actuated in the operating room, just prior to implant ofthe valve. Various designs are available, each of which require anaffirmative action which creates a risk that the operating room staffwill not completely constrict the commissure posts, possibly leading tosuture looping. To compound the problem, the devices sometimes requireseveral precise steps, which can be confusing in the pressuredenvironment of a heart surgery with the patient on bypass.

Despite a number of advances, there is still a need in the art for aholder and associated packaging for tissue-type prosthetic mitral valvesthat helps prevent suture looping and is more intuitive to use.

SUMMARY

The present application provides a holder and associated packagingsystem for prosthetic heart valves that is more intuitive to use andpre-constricts and/or pre-shields the commissure posts of the valve toprevent suture looping and ease implantation. Pre-constriction andpre-shielding mean at the time of manufacture, so that the valves arestored for at least 24 hours with the commissure posts constrictedand/or shielded. The valve may be bioprosthetic and stored dry to avoidcontinued cross-linking of the leaflets. Capping the glutaraldehydeterminates the cross-linking process by consuming all of the amineseliminating cross-linking sites for the aldehydes. In certainembodiments, the holders have solid legs that directly contact,constrict and hold the commissure posts without the use of sutures intension that might creep over the time in storage.

For an aortic valve, the holder may have a solid hub and legs on theoutflow end of the valve that retain the commissure posts inward. For amitral valve, the holder may have a base in contact with the inflow endand a shaft portion that projects through the valve leaflets andcooperates with movable legs on the outflow end of the valve in contactwith the commissure posts. Disclosed methods include constricting thevalve commissure posts and then packaging the valve in a sterilecontainer.

The present application also describes embodiments a valve holder for aprosthetic heart valve that shields the tips of the commissure postsduring implantation of the prosthetic heart valve at a native heartvalve annulus to prevent suture looping and ease implantation withoutnecessarily pulling or otherwise constricting the commissure postsradially inward. The holder can have a base in contact with an inflowend of a prosthetic valve and a shaft portion that projects through thevalve leaflets and cooperates with flexible members on an outflow end ofthe prosthetic valve to shield the tips of commissure posts. Disclosedmethods include shielding the valve commissure posts and then packagingthe valve in a sterile container along with the valve holder.

In one representative embodiment, a valve holder for a prosthetic heartvalve comprises a plurality of angularly spaced, leg members configuredto extend at least partially through the prosthetic valve in the outflowdirection. The leg members have distal end shielding portions and aremoveable between a radially outward position and a radially inwardposition, wherein when the leg members are in the radially outwardposition, the distal end portions extend over and shield the tips of thecommissure posts of the prosthetic valve and wherein when the legmembers are in the radially inward position, the distal end portions arespaced radially inward of the commissure tips and can be withdrawnthrough the prosthetic valve in a direction toward the inflow end.

In another representative embodiment, a prosthetic heart valve assemblycomprises a prosthetic heart valve and a valve holder. The prostheticheart valve has an inflow end, an outflow end, and plural commissureposts ending in tips projecting in an outflow direction. The valveholder comprises an inner body member and an outer shielding member. Theouter shielding member comprises a plurality of angularly spaced,flexible leg members, each having a proximal portion extending throughthe prosthetic valve and a distal end portion disposed over a tip of acorresponding commissure post. The inner body member comprises a shaftextending through the leg members and retaining the leg members in aradially outward position in which the distal end portions cover thetips of the commissure posts. Removal of the shaft from the leg membersin a direction toward the inflow end of the prosthetic valve the allowsthe leg members to flex to a radially inward position away from the tipsof the commissure posts to allow the leg members to be withdrawn throughthe prosthetic valve in a direction toward the inflow end.

In another representative embodiment, a method of implanting aprosthetic heart valve comprises providing a prosthetic heart valveassembly comprising a prosthetic heart valve and a valve holder. Theprosthetic valve has an inflow end, an outflow end, and pluralcommissure posts ending in tips projecting in an outflow direction. Thevalve holder comprises an inner body member and an outer shieldingmember. The outer shielding member comprises a plurality of angularlyspaced, flexible leg members, each having a proximal portion extendingthrough the prosthetic valve and a distal end portion disposed over atip of a corresponding commissure post. The inner body member comprisesa shaft extending through the leg members and retaining the leg membersin a radially outward position in which the distal end portions coverthe tips of the commissure posts. The method further comprisesdelivering and securing the prosthetic valve to a native valve annulusin the heart, retracting the inner body member through the inflow end ofthe prosthetic valve, causing the leg members to flex radially inwardlyaway from the commissure posts, and then retracting the shielding memberthrough the inflow end of the prosthetic valve.

In another representative embodiment, a method of packaging a prostheticheart valve comprises providing a prosthetic heart valve having aninflow end, an outflow end, and plural commissure posts ending in tipsprojecting in an outflow direction, and providing a shielding membercomprising a plurality of flexible leg members, each having a distal endportion. The leg members are inserted into the inflow end of theprosthetic valve until the distal end portions are distal to the tips ofthe commissure posts and the leg members are then bent or deflectedradially outward such that the distal end portions cover the tips of thecommissure posts. The prosthetic heart valve and the shielding membercan then be packaged for storage and/or shipping.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the present invention will become appreciatedas the same become better understood with reference to thespecification, claims, and appended drawings.

FIG. 1A is a top plan view of a prosthetic heart valve from an outflowend showing portions of an exemplary assembled valve holder of thepresent application secured thereto.

FIG. 1B is a sectional view taken along line 1B-1B in FIG. 1Aillustrating the valve holder extending through the heart valve andhaving movable legs that constrict commissure posts of the heart valveradially inward, and FIG. 1C is an enlarged view taken from FIG. 1Bshowing an upper end of the valve holder.

FIGS. 2A-2C are sectional views as in FIG. 1B showing several steps indetachment and removal of the valve holder from the prosthetic heartvalve.

FIGS. 3A and 3B illustrate alternative locking plugs for use in theexemplary heart valve holder of the present application.

FIGS. 4A and 4B are top plan and side elevational views, respectively,of an alternative constricting-type valve holder of the presentapplication assembled with a prosthetic heart valve, preferably foreither aortic or pulmonic implant.

FIG. 5 is a perspective view of a prosthetic heart valve depicting asuture looped around a tip of a commissure post of the prosthetic valveduring implantation of the prosthetic valve.

FIG. 6 is a perspective view of an exemplary assembled pre-shieldedprosthetic heart valve assembly comprising a valve holder extendingthrough the prosthetic heart valve and having a shielding member withdistal end portions extending over and shielding the commissure tips.

FIG. 7 is a side perspective view of the exemplary assembledpre-shielded prosthetic heart valve assembly of FIG. 6 with a main shaftof a delivery tool attached to an inflow end of a valve holder.

FIG. 8 is a perspective view of the exemplary pre-shielded prostheticheart valve assembly of FIG. 6 in a partially dis-assembled state inwhich the distal end portions are in a radially inward position and aninner shaft is partially retracted such that a tab on an inner shaftcontacts a base ring of the shielding member.

FIG. 9 is a perspective view of the exemplary pre-shielded prostheticheart valve assembly of FIG. 6 shown in a dis-assembled state apart fromthe prosthetic valve.

FIG. 10 is an exploded, perspective view of the exemplary pre-shieldedprosthetic heart valve assembly of FIG. 6.

FIG. 11A is a perspective view of an exemplary shielding member withdistal end portions in a relaxed, radially inward position.

FIG. 11B is a perspective view of the exemplary shielding member of FIG.11A with the distal end portions in a radially outward position.

FIG. 12 is a side perspective view of an alternative embodiment of apre-shielded prosthetic heart valve assembly in a dis-assembled state.

FIG. 13 is side perspective view of the valve holder of the assemblyshown in FIG. 12.

FIG. 14 is a perspective view of another embodiment of a pre-shieldedprosthetic heart valve assembly in an assembled state showing animplantation suture contacting the shielding portion of the assembly.

DETAILED DESCRIPTION

The present invention provides improved systems and methods forpackaging, storing and delivering prosthetic heart valves to reducecomplications during valve delivery. The prosthetic heart valves caninclude flexible, typically bioprosthetic, leaflets that coapt in theflowstream and are supported by a surrounding stent structure includingupstanding commissure posts. As is well known in the art, the peripheraledges of the leaflets, either separate or within a whole xenograftvalve, are secured to the surrounding stent structure including theupstanding commissure posts which are cantilevered in the outflowdirection. The commissure posts are capable of flexing to a certaindegree to accommodate the forces of fluid dynamics after implant. Theflexing of the commissure posts helps the flexible leaflets both closeand open at the appropriate time, and mimics the action of the naturalcommissures of the respective heart valve annulus. However, because thecommissure posts extend axially in the outflow direction, they presentproblems during delivery of the valve to the target implantation site.

The present application describes systems and methods forpre-constricting the upstanding commissure posts so that they flexradially inward and present a smaller radial profile during delivery ofthe valve by the surgeon to the target implantation site. The presentapplication also describes systems and methods for pre-shielding thetips of the upstanding commissure posts during delivery withoutnecessarily constricting the commissure posts. The prosthetic heartvalve assembly can include a holder and a plurality of flexible membersextending through the prosthetic valve and having distal end portionsextending over and shielding the tips of the commissure posts. The terms“pre-constricting” and “pre-constricted” refer to constriction of thecommissure posts prior to the operating room technicians opening thesterile packaging. Likewise, the terms “pre-shielding” and“pre-shielded” refer to shielding of the tips of the commissure postsprior to the operating room technicians opening the sterile packaging.In other words, the prosthetic heart valve and a holder thatpre-constricts and/or pre-shields the commissure posts emerges assembledfrom the packaging, substantially ready for connection to a deliveryhandle and delivery (after washing off any preserving solution ifnecessary).

The present application is useful for prosthetic heart valves havingcommissure posts for any implant site, but is particularly useful formitral and aortic valves. Furthermore, the present application describestechniques that are particularly useful with dry prosthetic tissue heartvalves that do not require liquid containment during storage. However,it is conceivable that the present application could be applicable to“wet” prosthetic heart valves if precautions are taken so that long-termstorage of the valves with the commissure posts constricted does notresult in distorted leaflets. For example, it is conceivable thatsynthetic leaflets may someday be successfully used which are not fixed,or cross-linked, and therefore might be stored wet. Alternatively,bioprosthetic leaflets that are fully fixed and are not affected bylong-term storage with the commissure posts constricted might benefitfrom the principles discussed here. In short, the type of prostheticheart valve or leaflets should not be considered limited unlessexplicitly stated by an applicable claim.

Now with reference to FIGS. 1A and 1B, a prosthetic heart valve 20 isshown assembled to a valve holder 22 of the present application. Theheart valve 20 includes an inlet end 24 and an outlet end 26 separatedalong a vertical flow axis through the middle of the valve. Acloth-covered frame assembly or support frame 28 defines a periphery andflow orifice of the valve and includes commissure posts 30 that projectgenerally axially in the outflow direction separated by arcuate cusps 32that curve in the inflow direction. Three flexible leaflets 34 couple tothe frame 28 and extend inward therefrom. The leaflets 34 attach alongan undulating line that follows the commissure posts 30 and cusps 32. Asuture-permeable sewing ring 36 surrounds the inflow end of the valve20, and may have a planar peripheral shape as shown or a shape whichundulates upward a short distance in the vicinity of the threecommissure posts 30.

It should be understood that the terms inflow/inlet and outflow/outletrefer to the direction of blood flow through the valve 20, which isupward in the orientation shown. Additionally, because the illustratedvalve 20 is for implanting at the mitral annulus, the outlet end 26 withthe projecting commissure posts 30 forms the leading or distal end ofthe valve during delivery, while the inlet end 24 is the trailing orproximal end. Thus, at least in the context of the heart valve 20 andholder 22 assembly of FIGS. 1-2, with regard to directions the termsinlet and proximal are synonymous, as are the terms outlet and distal.

As mentioned above, the prosthetic heart valve 20 and other prostheticheart valves described herein may comprise a number of existing heartvalves which have commissure posts 28, and the particular constructionof the heart valve aside from having commissure posts is not consideredto be an essential part of the present application. However, as will beexplained, bioprosthetic heart valves that are stored dry areparticularly suitable for integration with the disclosed holders andtechniques.

Techniques are known for drying and storing bioprosthetic heart valveswithout immersing them in a preservative solution. The term “dried” or“dry” bioprosthetic heart valves refers simply to the ability to storethose heart valves without the preservative solutions, and the term“dry” should not be considered synonymous with brittle or rigid. Indeed,“dry” bioprosthetic heart valve leaflets may be relatively supple evenprior to implant. There are a number of proposed methods for dryingbioprosthetic heart valves, and for drying tissue implants in general,and the present application contemplates the use of valves processed byany of these methods. A particularly preferred method of dryingbioprosthetic heart valves is disclosed in U.S. Patent Publication No.2008/0102439 to Tian, et al. An alternative drying method is disclosedin U.S. Pat. No. 6,534,004 to Chen, et al. Again, these and othermethods for drying bioprosthetic heart valves may be used prior toimplementing the storage techniques described herein.

One such strategy is to dehydrate the bioprosthetic tissue in aglycerol/ethanol mixture, sterilize with ethylene oxide, and package thefinal product “dry.” This process eliminates the potential toxicity andcalcification effects of glutaraldehyde as a sterilant and storagesolution. There have been several methods proposed to use sugar alcohols(i.e., glycerine), alcohols, and combinations thereof aspost-glutaraldehyde processing methods so that the resulting tissue isin a “dry” state rather than a wet state with excess glutaraldehyde.Glycerol-based methods can be used for such storage, such as describedin Parker et al. (Thorax 1978 33:638). Likewise, U.S. Pat. No. 6,534,004(Chen et al.) describes the storage of bioprosthetic tissue inpolyhydric alcohols such as glycerol. In processes where the tissue isdehydrated in an ethanol/glycerol solution, the tissue may be sterilizedby ethylene oxide (ETO), gamma irradiation, or electron beamirradiation.

More recently, Dove, et al. in U.S. Patent Publication No. 2009/0164005propose solutions for certain detrimental changes within dehydratedtissue that can occur as a result of oxidation. Dove, et al. proposepermanent capping of the aldehyde groups in the tissue (reductiveamination). Dove, et al. also describe the addition of chemicals (e.g.antioxidants) to the dehydration solution (e.g., ethanol/glycerol) toprevent oxidation of the tissue during sterilization (ethylene oxide,gamma irradiation, electron beam irradiation, etc.) and storage. Tissueprocessed in accordance with the principles disclosed in Dove, et al.will be termed, “capped tissue,” and therefore heart valves which usesuch tissue will be termed, “capped tissue valves.” Capping theglutaraldehyde terminates the cross-linking process by consuming all ofthe amines eliminating cross-linking sites for the aldehydes, and it isbelieved that this in conjunction with removing the tissue valve out ofthe cross-linking solution (e.g., glutaraldehyde) by storing dry is themost effective way to terminate the cross-linking process.

As seen in FIG. 1B, the valve holder 22 extends through the heart valve20 and has movable legs 40 that constrict the commissure posts 30 of theheart valve radially inward. More specifically, the valve holder 22comprises a relatively wide base portion 42 in contact with the inflowend 24 of the heart valve 20, and an axially elongated shaft portion 44extending in the distal direction from the base portion through theheart valve. The shaft portion 44 projects along the central axis anddistally beyond the leaflets 34 of the heart valve. The movable legs 40are arranged to pivot about a top end of the shaft portion 44, as willbe described below. There are three movable legs 40 corresponding toeach of the three valve commissure posts 30.

Each of the movable legs 40 has an outer end with a short finger 46 thatextends down on the outside of a respective commissure post 30. As seenin FIG. 1C, an inner end of each of the legs 40 has a pivot and a leverstructure permitting a locking plug 48 to actuate the leg 40. Morespecifically, the upper end of the holder shaft portion 44 includes astep 50 formed on an inner wall thereof. A fulcrum projection 52 on eachof the movable legs 40 seats on the step 50, while a lever projection 54extends radially inward therefrom. In the illustrated embodiment, thelocking plug 48 includes a larger diameter lower portion 60 and asmaller diameter upper portion 62 that creates a ledge 64 which receivesthe lever projections 54 of the movable legs 40, as shown in FIG. 1C.Tethers 66 connect the lever projections 54 to an upper end of thelocking plug 48. A pull wire 68 attached to the lower end of the lockingplug 48 permits the user to displace the locking plug in a proximaldirection.

FIGS. 1A and 1B illustrate the assembled prosthetic heart valve 20 andholder 22 as they are provided by the manufacturer in a sterile shippingcontainer or packaging. In this configuration, the valve commissureposts 30 are pulled inward and held by the movable legs 40 of the holder22. As seen from the outflow end in FIG. 1A, the leaflets 34 curl upsomewhat such that their coapting free edges 35 can be seen around theoutside of the holder shaft portion 44. After the commissure posts 30are permitted to flex outward into their functional positions, theleaflet free edges 35 extend generally radially inward from respectivecommissure posts toward the central axis in a trefoil configuration (notshown). As explained above, the prosthetic heart valve 20 is preferablystored dry with the bioprosthetic tissue used for the leaflets 34treated to enable storage without a liquid preservative. As such, theleaflets 34 are fully fixed and are not subject to ongoing cross-linkingin the preservative solution. Consequently, even though the leaflets 34are deformed somewhat from their functional shapes during storage, asseen in FIG. 1A, they will resume their proper functional shapes afterremoval of the holder 22.

It should be understood that the holder 22 with the legs 40 constrictingthe commissure posts 30 remains in place during delivery of mitral valve20 until the sewing ring 36 seats at the mitral annulus. Constriction ofthe commissure posts 30 is only required during delivery down the arrayof pre-installed anchoring sutures. The extent to which the commissureposts 30 are flexed and held inward from the time of manufacture dependssomewhat on the materials used for the cloth-covered support frame 28.That is, the support frame 28 (or components therein) has a materialstress limit that determines the maximum inward angle at which thecommissure posts 30 can be flexed and held for extended periods of time.Beyond that stress limit, some material including the metals used toconstruct heart valves would experience plastic or permanentdeformation. Polymer materials when stressed above a point that ischaracteristic of the material and the storage temperature mayexperience creep leading to permanent deformation and possiblymalfunction after implant. In one embodiment, the commissure posts 30assume a slight inward angle in their relaxed, functional configuration,and are flexed and held inward farther by the holder 20 by an additional15-30°. For instance, this translates into an additional inward bendingdistance of between about 4-5 mm for an average size valve, with theabsolute distance being somewhat smaller for smaller valves andvice-versa. Again, this angular deformation depends on the desiredradial delivery profile governed by the material stress limits in thesupport frame 28.

FIGS. 2A-2C are sectional views as in FIG. 1B showing several steps indetachment and removal of the valve holder 22 from the prosthetic heartvalve 20, which occurs after seating the heart valve against the targetannulus. FIG. 2A shows proximal displacement of the pull wire 68 andlocking plug 48. By virtue of the connecting tethers 66, this movementalso pulls the lever projections 54 on the movable arms 40 in a proximaldirection. The fulcrum projections 52 step 50 on the inside of theholder shaft portion 44, and cause the movable arms 40 to pivot inwardsas shown. This releases the fingers 46 of the arms 40 from therespective commissure posts 30, which therefore spring outward intotheir relaxed, functional positions.

FIG. 2B shows further proximal displacement of the pull wire 68 andlocking plug 48, which also pulls the movable arms 40 together andthrough a lumen 45 of the holder shaft portion 44. The moving parts ofthe holder 22 can therefore be removed completely from the implantationsite, possibly through a tubular handle 70. The handle 70 connects to aproximal sleeve 72 on the holder 22, and may be flexible to enablepassage through non-linear access channels.

Finally, FIG. 2C illustrates removal of the entire holder 22 from theprosthetic heart valve 20. In a preferred embodiment, no sutures areused to connect the holder 22 to the valve 20, the latter simply beingheld between the arms 40 and the base portion 42 of the holder, as inFIG. 1B. Alternatively, although not shown, connecting sutures may beplaced through the outer peripheral edge of the base portion 42 andthrough the valve sewing ring 36. By attaching both ends of eachconnecting suture to the holder 22, and providing a cut point or wellwhere the suture can be severed in the middle, each of the connectingsutures can be removed with the holder by simply severing the connectingsutures.

FIGS. 3A and 3B illustrate alternative locking plugs for use in theexemplary heart valve holder of the present application.

FIGS. 4A and 4B illustrate an alternative pre-constricting valve holder80 of the present application assembled with a prosthetic aortic heartvalve 82. As mentioned above, during delivery of aortic heart valves theinflow end is the leading or distal end, while the outflow end with itscommissure posts is the trailing or proximal end. As such, the valveholder 80 couples to the outflow end of the valve 82, or to the tips ofthe commissure posts 84. As before, the prosthetic valve 82 furtherincludes a support frame that defines three upstanding commissure posts84 alternating with three arcuate cusps 86. A cloth covering 88 isremoved on the right side to expose an exemplary support frameconstruction. Specifically, the support frame includes a wireform 90,typically metallic, and a stent 92, typically polymeric. Variousinternal constructions of valve support frames are known in the art, andthe illustrated embodiment should not be considered limiting.

The valve holder 80 includes a central hub 94 having a cavity 96 towhich a delivery handle (not shown) may be attached. Three legs 98extend outwardly and down at an angle around the outside of and indirect contact with each of the commissure posts 84, thus maintainingthe commissure posts inwardly constricted by an angle θ. The angle θ istaken from the line through the commissure posts 84 in their relaxed,functional configuration, which is slightly offset from the vertical byan angle α of about 5° as shown. In one embodiment, the commissure posts84 are flexed and held inward by the holder 20 by about 15-30°, whichagain depends on the desired radial delivery profile governed by thematerial stress limits in the support frame.

In one embodiment, the legs 98 of the holder 80 are secured to the tipsof the commissure posts 84 using sutures or similar expedient which canbe easily detached. Alternatively, the legs 98 may have retractablefeatures, such as small barbs, that enable them to hold the tips of thecommissure posts 84 during storage and delivery of the valve to thetarget implantation site, but enable quick release. Still further bandsor ties (not shown) around both the commissure posts 84 and legs 98 maybe used to hold the components together until time to release the valve.

The holder 80, and in particular the outwardly extending legs 98, shouldbe made of a material that will not creep significantly under constantload at the temperatures at which the valve will be stored. Metallicmaterials including stainless steel, cobalt chromium (CoCr), or titaniumwould be preferable, but also some polymers are acceptable if the creepresistance will not cause the commissure posts 84 to move significantlyduring storage. For instance, some high-temperature polymers likepolyetherimide may be suitable. Additionally, polymers may be reinforcedwith fibers to prevent creep. Alternatively, the holder can be designedwith a high area moment of inertia so the strain is minimized to reducecreep. Creep is a function of material, temperature and the level ofstress on the material so thick sections opposing the load from thestent posts could reduce the level of strain.

FIG. 5 shows an exemplary prosthetic heart valve 100 and depicts how asuture can become looped on a commissure post of the valve. Theprosthetic heart valve 100 comprises an inflow end, an outflow end,leaflets 102, a sewing ring 104 at the inflow end, and three commissureposts 106 projecting in an outflow direction and ending in tips 108. Inthe absence of shielding of the tips and/or constriction of the posts106 during delivery of the prosthetic heart valve 100, a suture 110 maybecome hooked on one or more of the commissure tips 108 of one of thecommissure posts 106, as depicted in FIG. 5.

FIGS. 6-10 show a prosthetic heart valve assembly 112 comprising theprosthetic heart valve 100 and a valve holder 114, according to anotherembodiment. As with the embodiment of FIGS. 1-4, the prosthetic heartvalve 100 used in this embodiment and other embodiments described hereincan comprise any number of existing prosthetic valves which havecommissure posts 106, and the particular construction of the prostheticvalve aside from having commissure posts is not considered to be anessential part of the present application.

The valve holder 114 is configured to shield the commissure post tips108 to protect against suture looping during delivery of the prostheticvalve to a native valve annulus. In particular embodiments, the valveholder 114 need not constrict the commissure posts 106 and insteadshield the commissure post tips during valve delivery while thecommissure posts can remain in their non-deflected, functional state.The valve holder 114 in the illustrated embodiment comprises an innerbody member 116 and an outer shielding member 118 that is disposedaround the inner body member in an assembled state. The inner bodymember 116 in the illustrated configuration comprises a base 120 and asubstantially cylindrical inner shaft 122 extending from the base 120.The inner shaft 122 can include a resilient tab 124 (see FIGS. 8-10),the purpose of which is described below. The shielding member 118 in theillustrated configuration comprises a base, or base ring 126, a centralopening 128 defined by the base ring 126 (see FIGS. 10, 11A-B), and aplurality of leg members 130 extending from the base ring 126.

As best shown in FIGS. 11A-11B, each leg member 130 has a respectiveproximal base portion 132 connected to the base ring 126, a respectivedistal end portion 134, and a respective intermediate portion 136extending between the base portion and the distal end portion. Theshielding member 118 desirably has the same number of leg members 130 asthere are commissure posts 106 of the prosthetic valve. Thus, there arethree such leg members 130 in the illustrated embodiment, although agreater or fewer number of leg members can be provided. The shaft 122can be formed with a plurality of longitudinally extending,circumferentially spaced slots 138 configured to at least partiallyreceive respective leg members 130 when the assembly is in the assembledstate (as shown in FIG. 6). The leg members 130 desirably are spaced outsubstantially evenly around the base ring 126 to mirror thecircumferential spacing of commissure posts 106 around the prostheticvalve 100.

The leg members 130 are normally biased to assume a radially inwardposition (FIG. 11A) and can flex or bend outwardly to a radially outwardposition (FIG. 11B). Thus, in the absence of any forces on the legmembers 130, they assume the inward position shown in FIG. 11A; this canbe referred to as the relaxed state of the leg members. However, whenthe shaft 122 of the inner body member 120 is inserted though theopening 128 of the base ring 128 and between the leg members 130, theleg members 130 are caused to deflect outwardly such that the distal endportions 134 are positioned to shield the commissure tips 108 (FIG. 6),as further described below. Conversely, removal of the shaft 122 fromthe space between the leg members 130 allows the leg members to flex orspring back to the radially inward position. In this manner, the legmembers 130 can be referred to as cantilevered springs.

The distal end portions 134 can have a radial thickness that is greaterthan those of proximal and intermediate portions of the leg members 130.In particular embodiments, the distal end portions 134 comprise curved,convex distal end surfaces 152 facing away from the commissure tips 108and are adapted to extent over and shield the commissure tips. Theintermediate portions 136 of the leg members can be relatively thinnerthan the distal end portions 134 and the base portions 132 to facilitatedeflection of the leg members between the deflected position (FIG. 11B)and non-deflected position (FIG. 11A).

To assemble the prosthetic valve 100 and the valve holder 114 in themanner shown in FIG. 6, the shielding member 118 is inserted through theprosthetic valve 100 (and the leaflets 102) until the distal endportions 134 extend beyond the commissure post tips 108 and the basering 126 abuts or is adjacent the sewing ring 104 of the prostheticvalve. The inner shaft 122 of the inner body member 116 can then beinserted through the central opening 128 and between the leg members 130such that the leg members 130 are aligned within respective slots 138 onthe shaft 122. The shaft 122 is pushed through the leg members 130 toforce the leg members and their distal end portions 134 into a radiallyoutward position such that the distal end portions 134 extend over andshield the tips 108 of the commissure posts 106. As shown in FIGS. 8-10,the outer surface of the inner shaft 122 can have a resilient tab 124projecting radially outwardly from the outer surface of the shaft. Thetab 124 is shaped to allow the tab 124 to pass underneath the base ring126 when the shaft 122 is inserted into the shielding member 118 yetengage the base ring 126 and prevent separation of the shaft 122 andshielding member 118 when the shaft is moved in the opposite direction.Thus, as the shaft 122 is inserted through the base ring 126 and betweenthe leg members 130, the base ring 126 can contact the titled or cantedoutermost surface of the tab 124, which forces the tab to flex inwardlyand allow the shaft 122 to be fully inserted between the leg members 130(FIG. 6). When the tab 124 passes the base ring 126, the tab 124 flexesor springs back radially outwardly to its relaxed state.

FIG. 7 is a side perspective view of the prosthetic heart valve assembly100 in an assembled state, showing placement of sutures 140 that securethe base 120 of the inner body member 116 to the base ring 126 of theshielding member 118. As shown, the proximal (inflow) surface 146 of thebase 120 can include a plurality of radially extending slots 142. Eachof the sutures 140 bridges across a respective slot and has two endportions that extend in the outflow direction through the base 120 andthe base ring 126. The ends of each suture 140 passing through the basering 126 can be tied together as shown at 144 so as to temporarilysecure the inner body member 116 to the shielding member 118. The base120 of the inner body member and the base ring 126 can have suture holesto allow the sutures 140 to pass through those components duringassembly. The distal end portions 134 of the leg members 130 can engagethe commissure tips 108 such that the prosthetic valve 100 is retainedin place around the shielding member 118. In alternative embodiments,the same or additional sutures may secure the base 120 and/or the basering 126 to the inflow end of the prosthetic valve 100 by, for example,threading the sutures through the sewing ring 104 of the prostheticvalve 100. The prosthetic valve 100 can be introduced into a patient'sbody and delivered to the desired implantation location (adjacent themitral valve) in the assembled state shown in FIGS. 6 and 7. In theassembled state, the commissure posts 106 of the prosthetic valve 100need not be bent or deflected inwardly and instead can be in anon-deflected, functional position for delivery into the body, as shown.

The proximal surface 146 of the base 120 of the inner body member 116can include a centrally located threaded bore or opening that canreceive the distal end portion of a shaft 148 of a delivery tool formanual delivery of the prosthetic heart valve assembly 100. The proximalend of the shaft 148 can be connected to a suitable handle formanipulation by a user. In other embodiments, the inner body member 116may have other attaching mechanisms for connecting the shaft of adelivery tool. The present invention is not limited with respect to thetype of delivery tool, handle or related apparatus or with respect tothe type of connection to the delivery tool. Once the user has attachedthe delivery tool, the prosthetic heart valve assembly 100 may bedelivered and secured to a native valve annulus in the heart such as themitral valve annulus.

FIG. 6 shows the prosthetic valve 100 and the holder 114 as they areprovided by the manufacturer in a sterile shipping container or package.The shaft of a delivery tool can be pre-attached to the holder 114 andpackaged together with the prosthetic valve and the holder. In otherembodiments, the delivery tool shaft can be packaged separately and canbe mounted to the valve holder by a user just prior to a procedure. Asnoted above, the prosthetic valve 100 can have “dry” tissue leaflets andcan be stored with the valve holder without a preserving solution. Assuch, any distortion of the leaflets 102 caused by the valve holderduring storage does not permanently deform the leaflets, which canassume their normal functional shape once removed from the valve holder.

Although less convenient for a user, it should be noted that theprosthetic valve 100 and the valve holder 114 can be packaged inseparate sterile containers or packages, in which case a user can mountthe prosthetic valve to the valve holder in the manner described abovejust prior to a procedure. For example, the valve holder 114 can also beused to implant a prosthetic valve that is stored in a preservingsolution. To avoid permanent leaflet deformation caused by thecross-linking process, it may be desirable to package the valve holder114 separate from a prosthetic valve stored in a preserving solution.

To deliver and secure the prosthetic valve 100 to a native valveannulus, the user can secure an array of sutures to the native valveannulus, thread the sutures through the sewing ring 104 of theprosthetic valve 100, and slide the prosthetic valve assembly 100 alongthe sutures until the prosthetic valve 100 sits against the native valveannulus, as known in the art. As noted above, suture looping can occurwhen one or more of the sutures in the parachute array inadvertentlywraps around the inside of one or more of the commissure post tips. Thedistal end portions 134 extend over the commissure post tips to protectagainst suture looping. The curved distal end surfaces 152 can contactand push the sutures away from the commissure post tips as theprosthetic valve is parachuted along the suture array.

FIGS. 8-9 show the process of disassembling the prosthetic heart valveassembly 100 and retracting the valve holder 114 from the prostheticvalve 100 once the prosthetic valve has been safely secured to a nativevalve annulus. First, the base 120 is mechanically disengaged from thebase ring 126 and, if applicable, the prosthetic heart valve 100 by, forexample, clipping the sutures 140 shown in FIG. 7. Next, as shown inFIG. 8, the inner body member 116, which may be connected to the shaft148 of a delivery tool, is retracted away from the prosthetic valve 100in the proximal direction as indicated by arrow 150. Retraction of theinner shaft 122 during this phase removes the outward radial force onthe leg members 130 such that the distal end portions 134 flex inwardlyof the commissure posts 106, thereby exposing the commissure tips 108.At this point or upon further withdrawal of the inner shaft 122, the tab124 comes into contact with and engages the base ring 126. From thispoint onwards, as the inner body member 116 is further retracted in theproximal direction, the tab 124 causes the shielding member 118 to beretracted along with the inner body member 116 away from the prostheticvalve 100. With the distal end portions 134 in their relaxed, radiallyinward states, the shielding member 118 can be retracted through theleaflets 102 and completely removed from the prosthetic valve 100 alongwith the inner body member 116, as shown in FIG. 9.

Although the inner shaft 122 is cylindrical and the central opening 128is circular in the illustrated embodiment, the inner shaft and thecentral opening can have other shapes. For example, the inner shaft 122can have a non-circular cross-sectional profile (in a planeperpendicular to its length) and the central opening 128 can be anon-circular shape, which can be the same or different shape than thecross-sectional profile of the inner shaft. Also, the inner shaft 122can have a cross-sectional profile that varies along its length, such asa tapered inner shaft 210 (FIGS. 12-13, described below). In particularembodiments, the distal end portions 134 of the leg members can contactthe commissure post tips 108, although in alternative embodiments theleg members can be configured such that there can be a small gap betweenthe commissure post tips 108 and the distal end portions 134.

The inner body member 116 and the shielding member 118 can be made ofany of various suitable materials, including metals or metal alloys(e.g., titanium, stainless steel, Nitinol, cobalt chromium alloys) orany of various polymeric materials, such as various polyamides,polyesters, or copolyesters. Some examples of polymers that can be usedto form the inner body member 116 and/or the shielding member 118include, without limitation, polyethylene terephthalate (PET),polytetrafluoroethylene (PTFE), or polyoxymethylene (POM). In a workingembodiment, the shielding member 118 is made of titanium and the innerbody member 116 is made of a suitable polymer.

In alternative embodiments, different techniques and/or mechanisms canbe used to flex or move the leg members 130 between the inward andoutward positions. For example, instead of an inner shaft 122, one ormore levers or linkages can be operatively coupled to each of the legmembers 130 to effect movement of the leg members between the inward andoutward positions. The handle of the delivery tool can include a switchor actuator that is operably coupled to the leg members via the one ormore levers or linkages such that activating the switch or actuator iseffective to move the leg members 130.

FIG. 12 shows an alternative embodiment of a prosthetic heart valveassembly 200 in a partially disassembled state comprising a prostheticheart valve 100 and a valve holder 202. FIG. 13 shows the valve holder202 apart from the prosthetic valve 100. As shown in FIGS. 12 and 13,the valve holder 202 in the illustrated embodiment comprises an innerbody member 204 and an outer shielding member 206. The inner body member204 can comprise a base 208 and an inner shaft 210 projecting from thebase 208. The inner shaft 210 can be tapered in a direction from thedistal end of the shaft toward the base 208 such that a distal portion212 of the shaft has a greater diameter than a proximal portion of theshaft adjacent the base 208. The base 208 can be connected to the distalend portion of a shaft 224 of a delivery tool. The shielding member 206can comprises a base ring 214 defining a central opening 216 and aplurality of leg members 218 connected to and extending from the basering 214. The leg members 218 can have wedge-shaped distal end portions220 configured to extend over and shield the commissure post tips 108during delivery of the prosthetic valve 100, as described above inconnection with the embodiment of FIGS. 6-11.

In order to place the shielding member 206 around the tapered shaft 210of the inner body member 204, the base ring 214 can be formed with aslit or gap 222. In this manner, the base ring 214 has a split-ringconfiguration that allows the base ring 214 to be splayed open andplaced around the inner shaft 210, as depicted in FIG. 13. In particularembodiments, the inner diameter of the ring 214 is slightly larger thanouter diameter of the proximal end portion of the inner shaft 210adjacent the base 208. In alternative embodiments, the base ring 214need not have a split ring configuration and instead the inner bodymember and the shielding member can be molded, machined or otherwiseformed in an assembled state with the shielding member pre-positionedaround the shaft 210.

To assemble the prosthetic valve 100 and the valve holder 202, the shaft210 is held in a partially retracted position relative to the shieldingmember 206 to allow the distal end portions 220 to remain in anon-deflected state (as depicted in FIGS. 12 and 13). With the shieldingmember and the inner body member in this position, the leg members 218can be inserted through the prosthetic valve 100 (and the leaflets 102)until the distal end portions 220 are distal to the commissure post tips108. Once the base ring 214 abuts the inflow end of the prosthetic valve100, the distal end portions 220 will be distal to, but still spacedradially inward of, the commissure post tips 108. The inner shaft 210can then be advanced toward distal end portions 220, causing the legmembers 218 to flex radially outwardly to position the distal endportions 220 over the commissure post tips 108. The distal end portion212 of the tapered inner shaft 210 can be curved or rounded as in FIGS.6-10 to assist in pushing the leg members 220 to the radially outwardposition as the shaft 210 is advanced through the shielding member. Onceassembled, the valve holder 202 and the prosthetic valve 100 can bepackaged together in a sterile container or package (with or without theshaft 224).

To disengage the valve holder 202 from the prosthetic heart valve 100after the prosthetic valve has been sutured to a native valve annulus,sutures connecting the base 208 to the base ring 214 (not shown) aresevered to disengage the inner body member 204 from the shielding member206. The inner body member 204 is then retracted using a delivery tool.As the inner shaft 210 is withdrawn, the force from the distal portionof the inner shaft 210 pushing against the leg members 218 is removed.The distal end portions 220 are then able to retract to a radiallyinward position, thereby exposing the commissure post tips 108. As theshaft 210 is further withdrawn, the outer surface of the shaft 210 comesinto contact with the base ring 214 at a location along the shaft wherethe outer diameter of the shaft 210 approximates the inner diameter ofthe central opening 216 of the base ring 214. In this manner, furtherretraction of the shaft 210 is effective to retract the shielding member206 back through and away from the prosthetic valve.

FIG. 14 shows an alternative embodiment of a prosthetic valve assembly300 comprising a prosthetic heart valve 100 and a valve holder 302. Thevalve holder 302 in the illustrated embodiment comprises a base 304, aninner shaft 306 extending from the base 304, and a deliver tool shaft308 connected to the opposite side of the base from the inner shaft 306.The valve holder 302 can further include a plurality of distal shieldingportions 310 spaced around the inner shaft 306. The distal shieldingportions 310 can, in a first state, be at least partially housed withinrespective radially extending slots (not shown) formed in the innershaft 324 and, in a second state, can project radially outward from theslots.

More specifically, during assembly of the prosthetic valve 100 and thevalve holder 302, the distal shielding portions 310 may be retainedinside the respective slots and/or the interior of the shaft such thatthe shielding portions 310 are spaced radially inwardly of thecommissure post tips 108. In this position, the inner shaft 306 and theshielding portions 310 can be advanced through the prosthetic valve 100(and the leaflets 102) toward the outflow end of the prosthetic valve.When the shielding portions 310 are advanced beyond the commissure posttips, the shielding portions 310 can be caused to project radiallyoutwardly from the slots to extend over and shield the commissure posttips, as depicted in FIG. 14. Various techniques and/or mechanisms canbe employed to cause the shielding portions 310 to project outwardlyfrom the slots. In one particular embodiment, for example, the shieldingportions 310 can be spring loaded and/or can be operatively connected toan actuator or switch on the handle by a linkage assembly or leverextending through the shaft 308. Actuating the actuator or switch causesthe shielding members 310 to project outwardly from the inner shaft 310to the position shown in FIG. 14.

The prosthetic valve 100 can be delivered and sutured to a native valveannulus in the heart using the valve holder 302 in the manner describedabove by sliding or parachuting the prosthetic valve 100 along an arrayof sutures secured to the native annulus. FIG. 14 shows a suture 314contacting the distal end of one of the shielding portions 310. As theprosthetic valve is advanced toward the native annulus, the shieldingportion 310 pushes or guides the suture 314 away from the commissurepost 106 to prevent the suture from looping around the adjacentcommissure post tip 108. Once the prosthetic valve 100 is secured to thenative valve annulus, the switch/actuator on the handle of the deliverytool may be activated to retract the shielding portions 310 radiallyinwardly into the slots and/or the interior of the inner shaft 306 sothat the shielding portions are spaced radially inwardly of thecommissure post tips, after which the valve holder may be retractedthrough the prosthetic valve 100 and withdrawn from the body.

In particular embodiments, holders of the present invention includemembers configured to shield and/or constrict the commissure postsradially inward without necessarily using sutures in tension. Sutures intension have been used in the past to constrict the commissure posts atthe time of surgery, but may be unsuitable for long-term storage due totheir tendency to creep over time. If sutures were used and they creepedand stretched while stored, the commissure posts could eventually flexoutward, thus defeating the intended purpose. In terms of time frame,all previous mechanisms for shielding or constricting the valvecommissure posts are designed to be actuated after removal from thesterile packaging and at the time of surgery. As a matter of goodsurgical practices, once a surgical implant has been removed fromsterile packaging it should be implanted relatively soon or discarded toprotect against contamination. Thus, for the purpose of definition,embodiments described herein in which the prosthetic valves and holderassemblies are pre-assembled with the commissure posts constrictedand/or shielded by portions of the holder and then stored for later userefers to storage over a duration of at least 24 hours, to exclude thoseprevious mechanisms designed to be actuated at the time of surgery.

While the invention has been described in its preferred embodiments, itis to be understood that the words which have been used are words ofdescription and not of limitation. Therefore, changes may be made withinthe appended claims without departing from the true scope of theinvention.

We claim:
 1. A method of manufacturing a prosthetic heart valve,comprising: providing a prosthetic heart valve having an inflow end,three flexible commissure posts ending in tips projecting in an outflowdirection, and bioprosthetic flexible leaflets connected to andsupported by the commissure posts; constricting and holding the threeflexible commissure posts radially inward; and packaging the prostheticheart valve with the constricted commissure posts for shipping.
 2. Themethod of claim 1, wherein the prosthetic heart valve is configured forimplant at the aortic annulus, and the step of constricting and holdingcomprises assembling a valve holder with the prosthetic heart valve, thevalve holder directly contacting and constricting and holding the threeflexible commissure posts radially inward.
 3. The method of claim 2,wherein the valve holder includes a central hub and three outwardlyprojecting legs that directly contact and constrict and hold the threeflexible commissure posts radially inward.
 4. The method of claim 1,wherein the step of constricting and holding comprises assembling avalve holder with the prosthetic heart valve, the valve holderconfigured to constrict and hold the three flexible commissure postsradially inward without using sutures in tension.
 5. The method of claim1, wherein the prosthetic heart valve is adapted for implant at themitral annulus and the valve holder has a base portion in contact withthe inflow end of the valve and a shaft portion that projects throughthe flexible leaflets and cooperates with movable legs of the valveholder located on an outflow end of the valve in direct contact with thecommissure posts.
 6. The method of claim 1, wherein the prosthetic heartvalve is packaged dry with no liquid.
 7. A method of implanting at anative valve annulus in the heart the prosthetic heart valvemanufactured in accordance with claim 1, comprising: removing theprosthetic heart valve with the constricted commissure posts from itspackaging; delivering the prosthetic heart valve to an implantationsite; and permitting the constricted commissure posts to flex outward.8. The method of claim 7, wherein the step of constricting and holdingcomprises assembling a valve holder with the prosthetic heart valve, thevalve holder directly contacting and constricting and holding the threeflexible commissure posts radially inward, and wherein the step ofdelivering includes delivering and securing the prosthetic heart valveto the native valve annulus with the valve holder attached to theprosthetic heart valve, and wherein the step of permitting includesdisengaging the valve holder from the commissure post tips, anddetaching the valve holder from the prosthetic heart valve.
 9. Themethod of claim 8, wherein delivering and securing the prosthetic heartvalve further comprises securing a plurality of sutures to the nativeannulus, threading the sutures through a sewing ring of the prostheticheart valve, and sliding the prosthetic heart valve with valve holderattached along the sutures until the sewing ring seats against thenative valve annulus, wherein the valve holder is configured to preventthe sutures from contacting and entangling with the tips of thecommissure posts.
 10. The method of claim 9, wherein the prostheticheart valve is adapted for implant at the mitral annulus and the valveholder has a base portion in contact with the inflow end of the valveand a shaft portion that projects through the flexible leaflets andcooperates with movable legs of the valve holder located on an outflowend of the valve in direct contact with the commissure posts.
 11. Amethod of manufacturing a prosthetic heart valve, comprising: providinga prosthetic heart valve having an inflow end, three flexible commissureposts ending in tips projecting in an outflow direction, andbioprosthetic flexible leaflets connected to and supported by thecommissure posts; and constricting and holding the three flexiblecommissure posts radially inward for at least 24 hours.
 12. The methodof claim 11, wherein the prosthetic heart valve is configured forimplant at the aortic annulus, and the step of constricting and holdingcomprises assembling a valve holder with the prosthetic heart valve, thevalve holder directly contacting and constricting and holding the threeflexible commissure posts radially inward.
 13. The method of claim 12,wherein the valve holder includes a central hub and three outwardlyprojecting legs that directly contact and constrict and hold the threeflexible commissure posts radially inward.
 14. The method of claim 11,wherein the step of constricting and holding comprises assembling avalve holder with the prosthetic heart valve, the valve holderconfigured to constrict and hold the three flexible commissure postsradially inward without using sutures in tension.
 15. The method ofclaim 11, wherein the prosthetic heart valve is adapted for implant atthe mitral annulus, and the constricting and holding comprisesassembling a valve holder with the prosthetic heart valve, the valveholder having a base portion in contact with the inflow end of the valveand a shaft portion that projects through the flexible leaflets andcooperates with movable legs of the valve holder located on an outflowend of the valve in direct contact with the commissure posts.
 16. Themethod of claim 11, wherein the prosthetic heart valve is dry and thestep of constricting and holding comprises assembling a valve holderwith the prosthetic heart valve and packaging the assembly dry with noliquid.
 17. A method of implanting the prosthetic heart valvemanufactured in accordance with claim 16, comprising: removing theprosthetic heart valve with the constricted commissure posts from itspackaging; delivering the prosthetic heart valve to an implantationsite; and permitting the constricted commissure posts to flex outward.18. The method of claim 17, wherein the step of constricting and holdingcomprises assembling a valve holder with the prosthetic heart valve, thevalve holder directly contacting and constricting and holding the threeflexible commissure posts radially inward, and wherein the step ofdelivering includes delivering and securing the prosthetic heart valveto a native valve annulus in the heart with the valve holder attached tothe prosthetic heart valve, and wherein the step of permitting includesdisengaging the valve holder from the commissure post tips, anddetaching the valve holder from the prosthetic heart valve.
 19. Themethod of claim 18, wherein delivering and securing the prosthetic heartvalve further comprises securing a plurality of sutures to the nativeannulus, threading the sutures through a sewing ring of the prostheticheart valve, and sliding the prosthetic heart valve with valve holderattached along the sutures until the sewing ring seats against thenative valve annulus, wherein the valve holder is configured to preventthe sutures from contacting and entangling with the tips of thecommissure posts.
 20. The method of claim 19, wherein the prostheticheart valve is adapted for implant at the mitral annulus and the valveholder has a base portion in contact with the inflow end of the valveand a shaft portion that projects through the flexible leaflets andcooperates with movable legs of the valve holder located on an outflowend of the valve in direct contact with the commissure posts.